Evaluating hazardous air pollutants in Australia

Richness, coverage and concentration of heavy metals in vascular epiphytes along an urbanization gradient

Richness, coverage and concentration of heavy metals in vascular epiphytes were analyzed in isolated trees along an urbanization gradient in Southern Brazil. A total of 20 phorophytes were sampled in the main street of each site. Concentrations of chromium, cadmium, lead, manganese, nickel and zinc were measured in the leaves of Tillandsia recurvata L. using Graphite Furnace Atomic Absorption Spectrophotometry. A decreasing gradient of epiphyte richness and coverage was observed as urbanization increased. Vehicle fleet and demographic density were the parameters most correlated with the reduction of epiphytic diversity. In T. recurvata, significantly higher values of cadmium, lead and zinc were recorded in the most urbanized areas, and were strongly related to the vehicle fleet and to the demographic density in these sites. The results demonstrated that these parameters could be applied to the diagnosis of environmental quality in urban areas, allowing standardized analyses in other regions.

Study of the air quality in industrial areas of Santa Cruz de Tenerife (Spain) by active biomonitoring with Pseudoscleropodium purum

A biomonitoring technique with terrestrial moss transplants (50 sampling sites in a regular grid) was used in an area of the city of Santa Cruz de Tenerife, close to an oil refinery and to an area of dense road traffic for a period of 2 months. The concentration of metals and metalloids (As, Cd, Hg, Ni, Pb and V) and 16 polycyclic aromatic hydrocarbons (PAHs) were determined. The density distribution was represented, the enrichment factors calculated and multifactorial analysis applied. In addition, contamination maps were elaborated on the basis of the bioconcentration obtained, and after confirming the existence of spatial structure, the response surfaces were represented. The results showed very high levels of contamination by Ni and V in the study area, with similar dispersal patterns observed for both. The concentrations of Cd, Hg, Pb and PAHs were lower. Active biomonitoring with terrestrial mosses was found to be a suitable technique for implementing inexpensive environmental monitoring programmes in urban and industrialized areas.